This invention relates generally to wheelchairs and, more particularly, to an anti-rollback system which acts to prevent bi-directional rollback of manually operated wheelchairs when positioned on inclines.
Many people who use wheelchairs experience difficulty when negotiating inclines and ramps because of the gravitational forces acting on the wheelchair when the user releases his or her grip on the propulsion ring while repositioning the hands for the next thrust of motion.
The present invention provides an anti-rollback system that allows wheelchair users the freedom of travelling up and down inclines without enlisting the assistance of others to do so. The anti-rollback system of the present invention includes a pair of non-rotatable axles fixed to the frame of a wheelchair, a pair of wheel hubs, each of which includes two sprags or one-way clutches mounted in opposing rotational directions therein, and a means for selectively engaging either or neither sprag with the associated axle. The user may thereby select normal operation of the wheelchair or anti-rollback in either the forward or reverse direction.